I asked the same question a couple of years ago and I have been trying and failing to find the answer today thanks to a recurrence. I remember one issue being that I didn't know how to define the problem, so it took a couple of tries before someone understood what I was asking and answered it.

So the good news is that there is an answer, but I remember that it involves manually amending each node that has the problem by cutting and pasting in a particular view. Not ideal, given that several nodes are affected and the problem occurs with different nodes every time I save and re-open the mindmap.

Ideally, someone can provide a permanent fix or let me know what triggers it because it is annoying the hell out of me. Fingers crossed.

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